I would say that the best selection that goes with the Deathwing would either be to take the Ravenwing Attack Squadron if you want to keep your force on the table limited; or the Ravenwing Strike Force if you want something a little more durable and more likely to last.
One thing to consider with the Deathwing Strike Force detachment over the Deathwing Redemption Force formation, is that you are not restricted in how many Dreadnoughts you can bring. Granted, the ones you have access to are a bit more expensive because they must be Venerable and in Drop Pods, but they are still an option.
If your Deathwing are focused on shooting, then the Attack Squadron would be a better choice. It will keep the points down, give you some good quality ranged anti-tank with attack bikes that can hide behind LOS blocking terrain, and gives you a lot of range to play with on the reliable Deep Strike. However, if you want to drop in and then beslubber some amphetamine parrot up in combat, go with the Ravenwing Strike Force. For 400pts you can take Sammael, 3 Black Knights, and a Darkshroud. Sammael is a well rounded HQ, and the Black Knights are a good combat unit that just gets better the more you put in there. If you keep the Darkshroud close to the Black Knights, you can have a 2+ re-rollable cover save. With a combination between their Scout move and the Strike Force's special rule, you can have them move 3' across the board and have them in an ideal position on turn two for when your Terminators come in; and the odds are in your favour that the bikes will survive, especially if you have Sammael in with the squad as well.
